1. Field
The present disclosure relates generally to high-speed data communications interfaces, and more particularly, to analysis of signaling in multi-wire, multi-phase data communication links.
2. Background
Manufacturers of mobile devices, such as cellular phones, may obtain components of the mobile devices from various sources, including different manufacturers. For example, an application processor in a cellular phone may be obtained from a first manufacturer, while the display for the cellular phone may be obtained from a second manufacturer. The application processor and a display or other device may be interconnected using a standards-based or proprietary physical interface. For example, a display may provide an interface that conforms to the Display System Interface (DSI) standard specified by the Mobile Industry Processor Interface Alliance (MIPI).
In a multi-wire interface, the maximum speed of the communication link and the ability of a clock-data recovery (CDR) circuit may be limited by the variability of transition times between symbols carried on the communication link, phase shifts between signals received from different wires of the communication link. In a multi-wire interface, and the like. Transitions on different wires may exhibit different variations of signal transition times. Traditional test and measurement systems may be unable to properly characterize the communications link when multiple transitions observed at the receiver occur at the symbol boundaries and when transition times are variable over short periods of time. For example, large transition time differences in multi-wire signals may obscure the eye opening in an eye pattern displayed by a high-speed digital storage oscilloscope.